Blasting shell



Nov. 17, 1931. s. s, LANlER, JR, ET AL 1,832,132

BLASTING SHELL Filed Jan. 14. 1928 Mmmm@ nvenior .aizer J2:

VzmIeS/afz Chard f Alorney CJ i fl il Nov. 17, 1931 nNiTED sTATEs PATENT oi-FicE STERLING S. LANIER, JR., AND CHARLES BLANCHARD, OF `NOZRTONVILLE, KENTUCKY BLASTING SHELL Application filed January 14, 1928.

Our invention relates to a new and improved blasting shell suitable for use in coal, ore and other mining operations and designed to utilize, as an explosive, the ordinary blasting` powder, dynamite or other like standard explosives adapted to be detonated by a fuse or detonator.

ln the use of our invention, it is contemplated that a drill hole will be provided in the face of the coal, ore, rock or other substance to be blasted which will, as a general rule, and especially in the case of coal, be undercut. In the prevailing practice for using explosives of the type which we will use in our improved blasting shell, the explosive is placed at the inner end of the drill hole and is tamped in position'by stemming, usually extending to the outer face of the wall to be shot. The stemming is expensive; it is often blown out result-ing in the production of windy shots; there is no direction or control exerted over the effect oi the explosion so that an unnecessarily large amount of explosive has to be used which frequently has a bad ef- Ylect on the roof and when used with coal it tends to unduly shatter the mass below it so that only a small amount of lump is produced.

Our invention contemplates placing the explosive charge in a shell preferably of the recoverable type closed at its outer end, except ior a i'use hole, and open at its inner end so that it will apply the full explosive forces over a restricted area at the back of the drill hole where they will produce the greatest eil'ect and thereby enable a smaller amount of explosive to produce the desired results with the minimum shattering effect on the coal.

A further object of our invention contemplates the cutting ofthe open end ofthe shell at an acutenngle toits long axis, thereby producing an end ot' the shell which can engage the end wall ot' the drill hole without at the same time setting the entire open end of the shell flush against such inner end of the drill hole, which is not desirable for best shooting effects.

A iurther object of our invention is to provide means to reduce to a minimum the amount ot .stemming or packing required to hold an explosive or was .shell in position and Serial No. 246,869.

to this end the shell is provided with expansible jaws adapted to be set to grip the Walls ot the drill hole and preferably associated with wedge means to increase their grip in proportion to the force exerted to displace the shell outwardly by the explosion or gas expansion, whereby we insure the shell being held positively against being blown out of the d-rill hole. l

Our invention contemplates the use of only a relatively small amount of stemming which is adapted to be mounted so as to be expanded into the small space normally left between the outer end of the shell and the drill hole and to grip the drill hole, the force of its gripping action being adapted to be increased responsive to the outward pressure exerted on the shell by the explosion, thus making it 'equal not only to the duty of holding in check I the gases of explosion but also where the shell is used to shoot very hard substances in which the jaw cannot take positive gripping eli'ect, this stemming can be used as a frictional meliilini for holding the shell in place in the drill Our invention also contemplates the provision of means for manually expanding the clamp jaws and the stemming after the shell has been inserted into the drill hole.

Our invention further contemplates providing the shell body with a tapering outer end adapted to engage the stemming, and the gripping jaws where used, in such manner .as to cause the outward movement of such taper end responsive to the explosion to expand them toward the walls ofthe drill hole. Moreover, if desired the tapered end may be reduced and threaded and receives a y set nut adapted to be run up after the shell is in place, thereby forcing the stemming and jaws inwardly along with the wedge end of the shell to initially expand them into. firm engagement with the walls of the drill hole.

Our invention further comprises the novel details of construction and arrangements of parts which, in their preferred embodiments v only, are illustrated in the accompanying drawings, in which Fig. 1 is a vertical sectional view through an undercut i'ace of coal showing our improved blasting shell inserted at the inner end of the drill hole with the expanding wrench in engagementtherewith to clamp itinitially in position.

Fig. 2 is a similar view enlarged showing the shell, partly broken away. in longitudinal cross-section with its outer tapered end in elevation and its jaws and stemming initially set to clamp the walls of the drill hole.

Fig. 3 is a cross-sectional view on the line III-III of Fig. 2.

Fig. 4 is a view of a modified type of shell having only a wedge outer end to expand the stemming.

Fig. 5 is a view of another type of shell without the wedge to act on the stemming.

Similar reference numerals refer to similar parts throughout the drawings.

. Inthe embodiment of our invention shown in Figs. -1 to 3 to illustrate its distinctive features of construction and operation, we show the shell as applied to the shooting of coal, 6 indicating the face of the coal undercut at 7 and having a drill hole 8 therein near the roof 9. The shell itself as shown is of the recoverable type. and is formed of steel orany suitable metal which is heavy and strongenough to withstand the explosive forces, and it is cylindrical and has a chambered end 10 open at one end, where it is cut on a slant, and closed at the other end by awall 11 through which a small hole 12 is drilled for the passage of the fuse or detonator wires. The solid end of the shell is bevelled at 13 and beyond the bevel it is formed with a taper end designated as 14 which, as shown, is seuare in transverse crosssection, has a gradual taper, and is of substantial length. At its end it is reduced and threaded to form the screw 15, the hole 12 extending axially through this screw. The faces of the wedge end 14 are provided with longitudinal undercutI grooves 16 which receive loosely T-heads 17 which slidably mount on each face a segmental clamping jaw 18, the outer peripheral surface of which is usually provided with circumferential serrations or teeth 19 set to bite into the coal when the shell is forced outwardly. The inner ends of the jaws are reversely bevelled to the bevel of the face '13 and thus provide a. V-shaped annular pocket in which the stemming or packing 2O `is wound. A nut :21 is adapted to be run up on the screw and to carry ahead of it a washer '2:2 which will engage the outer ends of the jaws 18 to force them up on the taper end 14. thereby wedging theminto clamping relationship with the drill hole and exerting an initial outward pressure against the packing 9.0.

'It is contemplated that the ordinary cartridge, dynamite. or blast powder charge.

will be inserted into the explosive chamber 23 formed in the chanihered end 10 of the shell and that the usual fuse, o1' detonator will be inserted at the inner end of the chamber 23 with the fuse o'r lead wires 24 passed outward through the hole 12. though shells may obviously be used. It is contemplated that a suitable wrench or tool will be used to run the nut 21 up after the shell has been inserted in the drill hole and for this purpose we show merely conventionally a tubular wrench the inner end of which is square or .polygonal in shape to match the nut 21. 'lhe fuse or lead wires can be run through this wrench and itcan be ,used to force the shell into the hole 8 until its bevellcd tip engages the end wall 2G of the drill hole which is its correct position for shooting. rl`hen by turning the wrench, the nut Zl'is forced inwardly, setting the jaws up on the taper end 11 and expanding the jaws and thc packing Q0. As much pressure as desired can be thus applied preliminarily to the packing and the clamp jaws and when the wrench is removed and the shell is exploded, yas it kicks outwardly itsl wedge end` 14 and the bevelled face 13 act to expand or force outwardly the jaws 18 and the packing 20. thereby causing them to grip the drill hole .wall and seal the restricted clearance beyond it and the shell with a force equal to the power of the explosion. The result is that a relatively small amount of packing will act. far more reliably to prevent windy shots than where a much greater amount is used in the absence of any means to wedge it in position responsive to the explosive force. The teeth 19 on the jaws are merely typical of gripping means on the jaws and where the same are "used with hard substances in which the teeth would not bitet the teeth may be omitted and the outer jaw surface provided with any means which will increase its frictional engagement with the drill hole wall'. The tip of the .bevelled end only engages the end wall 26 ofthe drill hole and it follows that sufficient space is provided for the initial expansion of the gases, but before these can escape they must travel outwardly through the Very restricted clearance left between the shell and drill hole before reaching the packing.

In Fig. 4 we show a simpler and less eX- pensive type of blasting shell 2T wherein the inner chambered end can be either bevelled, as shown, or left square, as itis shown in Fig. 5, and the outer end 28 is so formed that it will co-act with the stemming 29 when the shell is forced outwardly responsive to the explosion and will expand the stemming, thereby effectively packing the shell and more effectively holding it against heilig blown out of the drill hole. In Fig. 5 the simplest type of blasting shell 30 is shown. the shell having its inner end unbeveled and its outer end untapered. The chamber Q3 has conmiunication at its inner end with the fuse hole 12 leading axially sive in our shell we shot down 150% more coal per unit of explosive than when shooting in accordance with the previous existing practice of merely tamping the explosive into the inner end of the drill hole.

Though we have described with great particularity the details of the embodiment of the invention herein shown, it is not to be -construed that wel are limited thereto, as

changes in arrangement and substitution of equivalents may be made by those skilled in the art without departing from the invention as defined in the appended claims.

We have found that the confinement of the gases by the use of the non-explosive shell at the inner end of the drill hole brings about a more complete combustion of all gases which has the effect of eliminating or very greatly reducing` smoke, and this even when black powder is used. This is a very important advantage from the standpoint of safety to the miners and in the economv of time following a shot. for ordinarily, after a black powder shot. there is a dense cloud of black smoke which has been known to ignite from an open lamp and which the men are unable to breathe without injurious eii'ects. The elimination of smoke from black powder or other permissible powder will make it practical to use same as the explosive in nou-gaseous mines at anv time duringr` the day while the men are in the mine, which will be of great advantage.

Having thus described our invention. what we claim as new and desire to secure by Letters Patent. is

1. A miners blasting shell of the recoverable type. havingI in its bodv portion a. chamber open, towards the inner end of the drill hole and adapted to receive the e'xnlosive charge and its fuse or detonator. and having a reduced outer end carrying both stemming` and gripping means adapted to co-act with the wall surrounding the shell.

2. A miners blasting shell of the recoverable type, having in its bodv a cavitv adapted to receive the explosive charge and its fuse or detonator, and carrving both stemming and gripping means adapted to coact with the wall surrounding the shell. the shell carrving means adapted. responsive to outward pressure from the explosion, to expand said stemming and gripping means.

3. A miners blasting shell of the recoverable type, comprising a substantiallv cylindrical body recessed at its inner end to contain an explosive charge and having its outer end reduced and bevelled, and stemming on the reduced end adapted to be expanded by said bevelled end-portion shaped to ex-A pand the stemming as. the shell reacts from the explosion.

4. A miners blasting shell of the recoverable type, comprising a cylindrical metal body recessed to contain a charge of explosive, and reduced at its outer end to provide a seat for stemming, and means, carried by and adapted to co-act with said seat to initially expand the stemmin 5. A miners blasting shell of the recoverable type, comprising a substantially cylindrical body recessed to receive a charge of explosive, clamp jaws and packing mounted on the body, and screw actuated wedge means adapted to expand the jaws and packing into engagement with the surrounding walls of the drill hole.

In testimony whereof we aiiix our signatures.

' STERLING S. LANER, JR.

, CHARLES BLANCHARD. 

